I am trying to learn how to give better feedback.
On thing you might have tried would've been to take the beach tileset and add a B/C/D/E or such tileset with the purpose of a single tile with a darkening/lightening screentone-like pattern (look up how manga artists use screentones to shade and such). Have that as a passable 'grass/brush' tile and then have that on a higher layer than the water. This way, it will look like lighter/darker water and your character can walk on/in it with only half of their body showing so it looks like they are walking through water that is high, but not so high that they can't wade through. You might need to add some border tiles as well, but those would be pretty easy once you have a pattern to use.